US6216668B1 - Engine performance measuring method - Google Patents

Engine performance measuring method Download PDF

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Publication number
US6216668B1
US6216668B1 US09/440,923 US44092399A US6216668B1 US 6216668 B1 US6216668 B1 US 6216668B1 US 44092399 A US44092399 A US 44092399A US 6216668 B1 US6216668 B1 US 6216668B1
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United States
Prior art keywords
engine
fuel
compression brake
fuel injectors
test
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US09/440,923
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English (en)
Inventor
David James Haugen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Deere and Co
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Deere and Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Deere and Co filed Critical Deere and Co
Assigned to DEERE & COMPANY reassignment DEERE & COMPANY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HAUGEN, DAVID JAMES
Priority to US09/440,923 priority Critical patent/US6216668B1/en
Priority to CA002302657A priority patent/CA2302657A1/en
Priority to AT00123697T priority patent/ATE237127T1/de
Priority to ES00123697T priority patent/ES2191590T3/es
Priority to EP00123697A priority patent/EP1102051B1/de
Priority to DE50001691T priority patent/DE50001691D1/de
Priority to ZA200006566A priority patent/ZA200006566B/xx
Priority to JP2000349148A priority patent/JP3745956B2/ja
Publication of US6216668B1 publication Critical patent/US6216668B1/en
Application granted granted Critical
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
    • F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
    • F02D13/04—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation using engine as brake
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M15/00—Testing of engines
    • G01M15/04—Testing internal-combustion engines
    • G01M15/042—Testing internal-combustion engines by monitoring a single specific parameter not covered by groups G01M15/06 - G01M15/12
    • G01M15/044—Testing internal-combustion engines by monitoring a single specific parameter not covered by groups G01M15/06 - G01M15/12 by monitoring power, e.g. by operating the engine with one of the ignitions interrupted; by using acceleration tests

Definitions

  • This invention relates to a method for measuring engine performance, and more particularly, an engine performance measuring method which utilizes the capabilities of an electronically controlled fuel injected engine with compression brake units.
  • engine performance has been measured by placing the engine in a test cell and connecting it to a dynamometer.
  • Commercially available internal combustion engines are known which have an electronic control unit which controls fuel injectors and engine compression brake units.
  • a engine compression brake system When activated, a engine compression brake system converts the engine from a power generating device into a power absorbing device. This power absorbing capability of the engine compression brake may be varied by activating different numbers of compression brake units.
  • Each engine compression brake unit converts one or more cylinders of the engine into power absorbing units. It would be desirable to use the capabilities of engine compression brake units and electronic controls in order to measure engine performance without the need for a dynamometer.
  • an object of this invention is to provide a method for measuring engine performance without requiring a dynamometer.
  • a further object of the invention is to provide such a method which utilizes the capabilities of a fuel injected, compression brake engine which has an electronic control unit which controls fuel injection and compression braking.
  • an internal combustion engine includes a plurality of cylinders, a plurality of fuel injectors, compression brake units operatively associated the cylinders, an engine speed sensor and an engine control unit (ECU) for controlling the fuel injectors and the compression brake unit as a function of at least sensed engine speed.
  • ECU engine control unit
  • a method of measuring performance of the engine includes running the engine at a specified speed under no load, setting to zero a rate of fuel flow delivered by a selected one or more of the fuel injectors associated with the cylinders associated with the compression brake unit, increasing by a first amount a rate of fuel flow delivered by the other of the fuel injectors so that the engine runs at the specified engine speed, activating the compression brake unit associated with the selected fuel injectors so that the cylinders associated therewith absorbs power, and again increasing by a second amount a rate of fuel flow delivered by the other of the fuel injectors so that the engine runs at the specified engine speed.
  • This second amount of fuel flow rate increase thereby represents a performance characteristic of the engine.
  • FIG. 1 is a simplified schematic diagram of an engine/compression brake control system with which the present invention may be employed.
  • FIG. 2 is simplified logic flow diagram of the steps of the method of the present invention.
  • An engine/control system 10 includes an internal combustion engine 12 , such as a conventional Diesel engine, with a plurality of fuel injectors 14 , 16 , 18 , 20 , 22 and 24 , each associated with a corresponding engine cylinder 15 , 17 , 19 , 21 , 23 and 25 .
  • the engine/control system also includes a plurality of commercially available compression brake units 26 , 28 and 30 , each operatively associated with a corresponding pair of the cylinders.
  • An engine control unit (ECU) 32 receives signals from various sensors, including a crankshaft sensor 34 which supplies engine speed and crankshaft position signals. ECU 32 supplies control signals to the fuel injectors 14 - 24 and the compression brake units 26 , 28 and 30 . With these components, engine performance can be measured by performing the following method. The pass/fail criteria for percent fueling will vary from engine to engine, depending upon the friction and brake efficiency of the engine.
  • Vehicle speed must be set and remain at zero.
  • the ECU 32 must be set to maintain a constant engine speed of, for example, 1500 rpm.
  • the PTO (not shown) and the clutch (not shown) must be disengaged so that there is no load on the engine 12 .
  • the engine oil pressure must be within a specified range.
  • the method begins at step 102 which confirms that all three compression brake units 26 - 30 are inactive, that all six fuel injectors 14 - 24 are operative, and starts a Brake Test Mode Period timer. Then in step 104 , the fuel consumed by all six injectors is monitored, and in step 106 , after a Brake Test Averaging Delay time period, the fuel consumed by all six injectors during the Brake Test Mode Period is calculated and stored as “Test Fuel Flow 0 ”.
  • Step 108 then deactivate fuel Injectors 14 and 16 .
  • Step 110 cause a delay for a “Brake Start Delay” time period.
  • Step 112 then activate engine compression brake unit 26 (associated with injectors 14 and 16 and cylinders 15 and 17 , and starts a “Brake Test Mode Period” timer.
  • step 114 after a “Brake Test Averaging Delay” period, calculates the fuel consumed by the four firing injectors 18 - 24 during the Brake Test Mode Period and stores this result as Test Fuel Flow 1 & 2 , after which step 116 deactivates engine brake unit 26 .
  • Step 118 compares Test Fuel Flow 1 & 2 to Test Fuel Flow 0 , and if Test Fuel Flow 0 is not greater than 51% of Test Fuel Flow 1 & 2 (in a typical engine), then step 120 determines that engine brake 26 has failed. Otherwise, step 122 is executed. If, in step 122 , Test Fuel Flow 0 is not less than 38% of Test Fuel Flow 1 & 2 , then step 124 determines that there is an engine fault and causes the test to be repeated, otherwise, step 126 determines that engine brake unit 26 is operating correctly.
  • steps 102 - 116 could be repeated for each brake unit, and then steps 118 - 126 repeated three times, once for each of the brake units 26 , 28 and 30 .
  • the ECU sets the fuelling flow rate of fuel injectors 14 and 16 (associated with engine compression brake unit 26 ) to zero, and increases the fuelling of remaining four injectors 18 - 24 in order to maintain the specified engine speed.
  • compression brake unit 26 is activated, and the ECU 32 is again allowed to increase the fuel flow rate of remaining four injectors 18 - 24 in order to maintain the specified engine speed.
  • the amount fuel flow increase required to operate the pair of compression braked cylinders associated with injectors 14 and 16 is determined, and this second amount of fuel flow increase represents a performance characteristic of the engine.
  • the fuel flow rate signal from an electronic engine control unit can be used to represent the power generated by each cylinder.
  • the conversion of the above described method into a standard computer program language for execution by the ECU 32 will be evident to one with ordinary skill in the art.
  • the percent increase in fuel flow rate for injectors 18 - 24 does not exceed a predefined limit, two possibilities are the potential cause.
  • the engine compression braking system is faulty, or second, the four power generating cylinders 19 - 25 are delivering less power than they should be generating.
  • the three compression brake units 26 , 28 and 30 it can be determined if a particular pair of cylinders are low in producing power (since for each brake unit, a different pair of cylinders will be generating power), or if a particular compression brake unit is absorbing less power than it should be absorbing.
  • the functionality of the engine compression brake system can be tested, and it can be determined if a pair of engine cylinders is producing less power then normal.
  • This method does not require any additional equipment on the engine. It requires only the engine compression brake system and an engine control unit. This method can be used not only for a post-production test, but it can also be used to test performance in the field, such as in a field service mode for engine and compression brake diagnostics.
  • This method can be applied to any engine that has the capability of independently controlling the fuelling of some cylinders while simultaneously operating a engine compression brake on the other cylinders. Furthermore, this concept can also be applied to engines which have a separate engine compression brake for each cylinder. For example, in a six cylinder engine equipped with six engine compression brake units, if one brake is activated and the other five cylinders were supplied with fuel, the power delivered by the engine might normally be 68% to 71% of full power at the same engine speed. In a six cylinder engine equipped with engine compression brakes that activates two cylinders at a time, if the other four cylinders are fuelled, the power delivered by the engine might normally be 36% to 42% of full power at the same engine speed.
  • the power absorption resulting from the activation of an engine compression braking unit is a function of the engine speed, the pressure in the intake manifold (not shown), the engine compression ratio, the lift-profile-timing of the camshaft (not shown) and the lash adjustment (not shown) of the compression brake unit.
  • the only variable that changes with engine operation is the engine speed. For a given engine speed, a certain power absorption should occur for a pair of activated engine compression brake units.

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  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)
  • Testing Of Engines (AREA)
  • Oscillators With Electromechanical Resonators (AREA)
  • Stereophonic System (AREA)
  • Vehicle Body Suspensions (AREA)
  • Hybrid Electric Vehicles (AREA)
  • Valves And Accessory Devices For Braking Systems (AREA)
  • Mechanical Control Devices (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
US09/440,923 1999-11-16 1999-11-16 Engine performance measuring method Expired - Lifetime US6216668B1 (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US09/440,923 US6216668B1 (en) 1999-11-16 1999-11-16 Engine performance measuring method
CA002302657A CA2302657A1 (en) 1999-11-16 2000-03-28 Engine performance measuring method
EP00123697A EP1102051B1 (de) 1999-11-16 2000-10-31 Verfahren zur Ermittlung von Kennwerten eines Antriebs
ES00123697T ES2191590T3 (es) 1999-11-16 2000-10-31 Procedimiento para establecer valores caracteristicos de un accionamiento.
AT00123697T ATE237127T1 (de) 1999-11-16 2000-10-31 Verfahren zur ermittlung von kennwerten eines antriebs
DE50001691T DE50001691D1 (de) 1999-11-16 2000-10-31 Verfahren zur Ermittlung von Kennwerten eines Antriebs
ZA200006566A ZA200006566B (en) 1999-11-16 2000-11-13 Engine performance measuring method.
JP2000349148A JP3745956B2 (ja) 1999-11-16 2000-11-16 エンジン性能計測方法

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US09/440,923 US6216668B1 (en) 1999-11-16 1999-11-16 Engine performance measuring method

Publications (1)

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US6216668B1 true US6216668B1 (en) 2001-04-17

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US09/440,923 Expired - Lifetime US6216668B1 (en) 1999-11-16 1999-11-16 Engine performance measuring method

Country Status (8)

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US (1) US6216668B1 (ja)
EP (1) EP1102051B1 (ja)
JP (1) JP3745956B2 (ja)
AT (1) ATE237127T1 (ja)
CA (1) CA2302657A1 (ja)
DE (1) DE50001691D1 (ja)
ES (1) ES2191590T3 (ja)
ZA (1) ZA200006566B (ja)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030041658A1 (en) * 2001-09-04 2003-03-06 Leman Scott A. Method of determining fuel injector performance in-chassis and electronic control module using the same
US6535810B2 (en) * 2000-02-17 2003-03-18 General Electric Company System and process for detection of weak cylinders in a diesel engine
US6568367B2 (en) * 2001-07-31 2003-05-27 Caterpillar Inc Engine compression release brake system and method of operation
EP1359307A2 (en) * 2002-04-26 2003-11-05 Caterpillar Inc. On-board determination of fuel injector performance
US20030236609A1 (en) * 2000-02-17 2003-12-25 Cecil Daniel System and process for detection of weak or non-functioning cylinders in engines
US20050061299A1 (en) * 2001-09-04 2005-03-24 Leman Scott A. Determination of fuel injector performance in chassis
US6892569B2 (en) 2001-12-20 2005-05-17 Caterpillar Inc. In-chassis engine compression release brake diagnostic test and electronic control module using the same
US7353795B1 (en) * 2007-02-28 2008-04-08 Detroit Diesel Corporation Method for cylinder diagnostic test in an internal combustion engine
US20080092836A1 (en) * 2006-10-18 2008-04-24 Mutti James H Variable valve performance detection strategy for internal combustion engine
US20080141957A1 (en) * 2006-12-15 2008-06-19 Kevin Dea Valve performing detection and modification strategy for internal combustion engine
US7596992B2 (en) * 2007-07-25 2009-10-06 Denso Corporation Fuel injection control apparatus designed to compensate for deviation of quantity of fuel sprayed from fuel injector
EP2212533A1 (en) * 2007-10-22 2010-08-04 Volvo Lastvagnar AB Engine brake detection
CN105275654A (zh) * 2014-06-13 2016-01-27 丰田自动车株式会社 用于内燃发动机的控制装置
EP3184762A1 (en) * 2015-12-22 2017-06-28 Scania CV AB A method for checking the function of a compression release brake system
WO2022050841A1 (en) * 2020-09-04 2022-03-10 Daf Trucks N.V. Method for testing a decompression engine brake system; combustion engine and vehicle

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2826692B1 (fr) * 2001-06-28 2003-10-03 Renault Vehicules Ind Procede et systeme de commande d'un moteur comportant un frein a decompression

Citations (6)

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Publication number Priority date Publication date Assignee Title
USRE33450E (en) * 1987-10-13 1990-11-20 Dynanometer engine performance analyzer system
US5483927A (en) * 1993-08-27 1996-01-16 Detroit Diesel Corporation Method for engine control
US5647318A (en) 1994-07-29 1997-07-15 Caterpillar Inc. Engine compression braking apparatus and method
US5718199A (en) * 1994-10-07 1998-02-17 Diesel Engine Retarders, Inc. Electronic controls for compression release engine brakes
US5733219A (en) * 1996-05-13 1998-03-31 Caterpillar Inc. Apparatus and method for disabling a compression brake system
US5816665A (en) * 1997-01-10 1998-10-06 Caterpillar Inc. Compression and fluid retarding vehicle braking control system

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US4870585A (en) * 1987-10-13 1989-09-26 Manzolini David B Dynamometer engine performance analyzer system
US5925557A (en) 1994-09-29 1999-07-20 The Regents Of The University Of California DNA encoding mitogen activated protein kinase, FRK

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE33450E (en) * 1987-10-13 1990-11-20 Dynanometer engine performance analyzer system
US5483927A (en) * 1993-08-27 1996-01-16 Detroit Diesel Corporation Method for engine control
US5647318A (en) 1994-07-29 1997-07-15 Caterpillar Inc. Engine compression braking apparatus and method
US5718199A (en) * 1994-10-07 1998-02-17 Diesel Engine Retarders, Inc. Electronic controls for compression release engine brakes
US5733219A (en) * 1996-05-13 1998-03-31 Caterpillar Inc. Apparatus and method for disabling a compression brake system
US5816665A (en) * 1997-01-10 1998-10-06 Caterpillar Inc. Compression and fluid retarding vehicle braking control system

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6996467B2 (en) 2000-02-17 2006-02-07 General Electric Company System and process for detection of weak or non-functioning cylinders in engines
US6889133B2 (en) 2000-02-17 2005-05-03 General Electric Company System and process for detection of weak or non-functioning cylinders in engines
US20050222749A1 (en) * 2000-02-17 2005-10-06 Cecil Daniel System and process for detection of weak or non-functioning cylinders in engines
US20030236609A1 (en) * 2000-02-17 2003-12-25 Cecil Daniel System and process for detection of weak or non-functioning cylinders in engines
US6535810B2 (en) * 2000-02-17 2003-03-18 General Electric Company System and process for detection of weak cylinders in a diesel engine
US6568367B2 (en) * 2001-07-31 2003-05-27 Caterpillar Inc Engine compression release brake system and method of operation
US6732577B2 (en) * 2001-09-04 2004-05-11 Caterpillar Inc Method of determining fuel injector performance in-chassis and electronic control module using the same
US7025047B2 (en) 2001-09-04 2006-04-11 Caterpillar Inc. Determination of fuel injector performance in chassis
US20030041658A1 (en) * 2001-09-04 2003-03-06 Leman Scott A. Method of determining fuel injector performance in-chassis and electronic control module using the same
US20050061299A1 (en) * 2001-09-04 2005-03-24 Leman Scott A. Determination of fuel injector performance in chassis
US6892569B2 (en) 2001-12-20 2005-05-17 Caterpillar Inc. In-chassis engine compression release brake diagnostic test and electronic control module using the same
EP1359307A3 (en) * 2002-04-26 2005-02-23 Caterpillar Inc. On-board determination of fuel injector performance
US6748928B2 (en) 2002-04-26 2004-06-15 Caterpillar Inc In-chassis determination of fuel injector performance
EP1359307A2 (en) * 2002-04-26 2003-11-05 Caterpillar Inc. On-board determination of fuel injector performance
US7707977B2 (en) 2006-10-18 2010-05-04 Caterpillar Inc. Variable valve performance detection strategy for internal combustion engine
US20080092836A1 (en) * 2006-10-18 2008-04-24 Mutti James H Variable valve performance detection strategy for internal combustion engine
US7634981B2 (en) 2006-12-15 2009-12-22 Caterpillar Inc. Valve performing detection and modification strategy for internal combustion engine
US20080141957A1 (en) * 2006-12-15 2008-06-19 Kevin Dea Valve performing detection and modification strategy for internal combustion engine
US7353795B1 (en) * 2007-02-28 2008-04-08 Detroit Diesel Corporation Method for cylinder diagnostic test in an internal combustion engine
US7596992B2 (en) * 2007-07-25 2009-10-06 Denso Corporation Fuel injection control apparatus designed to compensate for deviation of quantity of fuel sprayed from fuel injector
EP2212533A1 (en) * 2007-10-22 2010-08-04 Volvo Lastvagnar AB Engine brake detection
US20100258079A1 (en) * 2007-10-22 2010-10-14 Volvo Lastvagnar Ab Engine brake detection
EP2212533A4 (en) * 2007-10-22 2012-01-18 Volvo Lastvagnar Ab MOTOR BRAKE DETECTION
US8312861B2 (en) 2007-10-22 2012-11-20 Volvo Lastvagnar Ab Engine brake detection
CN105275654A (zh) * 2014-06-13 2016-01-27 丰田自动车株式会社 用于内燃发动机的控制装置
EP3184762A1 (en) * 2015-12-22 2017-06-28 Scania CV AB A method for checking the function of a compression release brake system
WO2022050841A1 (en) * 2020-09-04 2022-03-10 Daf Trucks N.V. Method for testing a decompression engine brake system; combustion engine and vehicle
NL2026412B1 (en) * 2020-09-04 2022-05-04 Daf Trucks Nv Method for testing a decompression engine brake system; combustion engine and vehicle

Also Published As

Publication number Publication date
JP3745956B2 (ja) 2006-02-15
CA2302657A1 (en) 2001-05-16
EP1102051A3 (de) 2002-01-02
ATE237127T1 (de) 2003-04-15
DE50001691D1 (de) 2003-05-15
JP2001182551A (ja) 2001-07-06
ES2191590T3 (es) 2003-09-16
ZA200006566B (en) 2002-05-13
EP1102051B1 (de) 2003-04-09
EP1102051A2 (de) 2001-05-23

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